The definitive source for rare cactus collectors
Encyclopedic care guides, species profiles, field number collector logs and everything else you’ll need to know about taking care of your collection.
Field number database
Every cactus collected from the wild carries a code: FR 207, L 756, PP 1368. Trace any specimen back to the collector, the date, the locality, the GPS pin.
A cactus collector field-number database is a tool used to identify wild specimens by searching for collector acronyms and field numbers — for example, FR 207 refers to the 207th plant logged by Friedrich Ritter, a Copiapoa cinerea he found near Taltal, Chile in 1954. Each record traces the plant back to where it was collected (locality), the date collected, and the collector's name — acting as a "birth certificate" for the specimen.
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The rarity index
Inside the rarity index
Not all rare cacti are equally rare. Our list of the rarest cactus plants in the world ranks specimens by wild population, cultivation difficulty, and trade availability.
Explore the index →